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%I
%S 1023456789,1023456798,1023456879,1023456897,1023456978,1023456987,
%T 1023457689,1023457698,1023457869,1023457896,1023457968,1023457986,
%U 1023458679,1023458697,1023458769,1023458796,1023458967,1023458976,1023459678,1023459687,1023459768
%N Pandigital numbers: numbers containing the digits 0-9. Version 1: each digit appears exactly once.
%C This is a finite sequence with 9*9!=3265920 terms: a(9*9!)=9876543210.
%C A171102 is the infinite version, where each digit must appear at least once.
%C Subsequence of A134336 and of A178403; A178401(a(n)) = 1. [_Reinhard Zumkeller_, May 27 2010]
%C Smallest prime factors: A178775(n) = A020639(a(n)). [_Reinhard Zumkeller_, Jun 11 2010]
%C A178788(a(n)) = 1. [_Reinhard Zumkeller_, Jun 30 2010]
%C All these numbers are composite because the sum of the digits, 45, is divisible by 9. - T. D. Noe, Nov 09 2011
%C This is the 10th row of the of the array T(k,n) = n-th number in which the number of distinct base 10 digits is k. A031969 is the 4th row. A220063 is the 5th row. A220076 is the 6th row. A218019 is the 7th row. A219743 is the 8th row. [Jonathan Vos Post, Dec 05 2012]
%C From _Hieronymus Fischer_, Feb 13 2013: (Start)
%C The sum of all terms is 9!*49444444440 = 17942399998387200.
%C General formula for the sum of all terms of the finite sequence of the corresponding base-p pandigital numbers with p places: sum = ((p^2 - p - 1)*(p^p - 1) + p - 1))*(p-2)!/2.
%C General formula for the sum of all terms (interpreted as decimal permutational numbers with exactly d+1 different digits from the range 0..d < 10): sum = (d+1)!*((10d - 1)*10^d - d + 1)/18, d>1.
%C (End)
%H Robert G. Wilson v, <a href="/A050278/b050278.txt">Table of n, a(n) for n = 1..1000</a>.
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/PandigitalNumber.html">Pandigital Number</a>
%F A050278 = 9*A171571. - M. F. Hasler, Jan 12 2012
%F A050278(n) = A171102(n) for n <= 9*9!.
%t Select[ FromDigits@# & /@ Permutations[ Range[0, 9]], # > 10^9 &, 20] (* Robert G. Wilson v, May 30 2010, Jan 17 2012 *)
%o (PARI) A050278(n)={ my(b=vector(9,k,1+(n+9!-1)%(k+1)!\k!), t=b[9]-1, d=vector(9,i,i+(i>t)-1)); for(i=1,8, t=10*t+d[b[9-i]]; d=vecextract(d,Str("^"b[9-i]))); t*10+d[1]} \\ - M. F. Hasler, Jan 15 2012
%o (PARI) is_A050278(n)={ 9<#vecsort(Vecsmall(Str(n)),,8) & n<1e10 } /* assuming that n is a nonnegative integer */ - M. F. Hasler, Jan 10 2012
%Y Cf. A171102, A050288, A050289.
%Y Cf. A199630, A199631, A114260, A199632, A199633.
%Y Cf. A031969, A050278, A220063, A220076, A218019, A219743.
%K nonn,base,fini
%O 1,1
%A _Eric W. Weisstein_
%E Edited by _N. J. A. Sloane_, Sep 25 2010 to clarify that this is a finite sequence.
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